4. Patients with a pre-bronchodilator FEV1 ( forced expiratory volume in 1 second) value of 40% to 90% of individual predicted value at screening and at randomization, and the value at the randomization should be within 15% of the screening FEV1. The results of spirometry should meet the ATS/ERS ( American Thoracic Society/European Respiratory Society) criteria for acceptability and repeatability.